How can tartar and plaque be removed from teeth without grinding? is there any paste, etc. for it?
The girders of a suspension bridge form an arc. The definition of an arc is a curve or bowed shape, like a part of a circle. An example of an arc is a rainbow. To arc is defined as to make a curved shape or move in a curved path.
The arc is convex toward the ocean and concave toward the continent with a deep trench running parallel to the arc along the convex (ocean) side. Arcs and trenches are hundreds of miles long. Some well-known examples of island arcs are Japan, Aleutian Islands of Alaska, Mariana Islands, all of which are in the Pacific, and the Lesser Antilles in the Caribbean.